Adjustable ergonomic brace

ABSTRACT

A knee brace has push button actuatable stops, wherein the stops are biased outward into angular locking positions and inwardly directed pressure on the push buttons releases the stops and permits angular adjustment of the stops. A pair of catch plates with locking recesses facing inward, are provided, and outwardly biased locking pins engage the recesses in both catch plates. Each of the stop assemblies has an outwardly directed plate extending over the outer cover plate, and this plate is coupled to the physical stop member around the outer edge of the outer cover plate. The cover plate has angular indicia thereon, which may be viewed through windows in the outwardly extending plate portions of the stop assemblies.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.11/384,630, filed on Mar. 20, 2006, now U.S. Pat. No. 7,534,220, grantedon May 19, 2009, which is a continuation-in-part of U.S. applicationSer. No. 10/675,324, filed on Sep. 29, 2003, now U.S. Pat. No.7,037,287, granted on May 2, 2006.

FIELD OF THE INVENTION

This invention related to ergonomic knee braces.

BACKGROUND OF THE INVENTION

In the field of adjustable knee braces or supports, it is desirable thatthe brace include arrangements for limiting the movement of the lowerleg relative to the upper leg both as to bending the knee or flexion,and as to extension of the lower leg relative to the upper leg. Variousknee brace arrangements have been proposed, and these have includedupper struts for extending along the thigh, and lower struts forextending along the lower leg or calf. These are normally provided bothon the inside or medial side of the leg and also on the outer or lateralside of the leg; and the medial and lateral struts are normally padded,and provided with straps to hold them in place. Pivoting arrangementsare provided for coupling the upper and lower struts, and stops areprovided for limiting both extension and flexion of the knee.

The prior art patents in the filed of knee braces include U.S. Pat. No.5,672,152 granted Sep. 30, 1997; U.S. Pat. No. 5,921,946, granted Jul.13, 1999; U.S. Pat. No. 4,817,588, granted Apr. 14, 1989, U.S. Pat. No.4,953,543 granted Sep. 4, 1990, and U.S. Pat. No. 4,620,532 granted Nov.4, 1986. Although many of the foregoing provided useful results, theseprior art knee braces had shortcomings, in that they were unduly bulky,or were not simple to adjust, or did not have as many stop increments aswould be desired, or were otherwise not ergonomically configured.

SUMMARY OF THE INVENTION

Accordingly, objects of the invention include providing a knee bracewhich is compact, easy to use, which has many points of adjustment andis otherwise ergonomically configured. Preferably the adjustments shouldbe simple and natural so that there is no need to resort to collateralwritten instructions.

Initially, relative to an illustrative preferred embodiment of thepresent knee brace, the knee brace stop construction operates at theperiphery of the pivot arrangements so that the number of stopincrements is maximized for the size of the pivot discs. Secondly, thestops may be operated by simple inward pressure on a push buttonassociated with the flexion stop or the extension stop, to release thestop, followed by rotation of the stop to virtually any desired angle,and then followed by release of the push button to permit locking of thestop in the new angular position. With this simplified ergonomicconstruction, the stop adjustments may be easily made while the brace ismounted on the leg; and the mode of accomplishing stop adjustments issubstantially self evident, with the shifting of the stops resulting inthe natural or expected angular change in flexion or extension stops.

In order to achieve the foregoing results in one illustrativeembodiment, the pivoting assembly interconnecting the upper and lowerstruts includes, for both extension and flexion, at least one generallycircular or arcuate catch plate with stop recesses facing or openinginward toward the center of the assembly, and a movable stop memberpivoted at the center of the assembly and having an outwardly biasedlocking member for selectively engaging one of the stop recesses, andwith the locking member attached to a release button which extendsradially outward to the periphery of the pivot assembly.

Viewed from a different aspect, the pivoting assembly may include anouter cover or closure plate and an inner cover or closure plate; anarcuately configured array of locking steps; a movable stop memberpivoted at the center of the assembly and having an outwardly biasedlocking member for selectively engaging at least one of the lockingsteps; and with the locking member attached to a release button which islocated radially outward at the periphery of the pivot assembly.

Additional features may include the provision of angular indicia on theouter surface of the outer one of said cover or closure plates and theimplementation of the movable stop assembly by an outer, radiallyextending flat support member adjacent the indicia, preferably with awindow through which the angular indicia may be seen. Further, themovable stop assembly may extend over the edge of one of said platesinto the space between the two cover plates to cooperate with thelocking steps. This construction contributes to the relatively thinoverall configuration of the pivoting assembly, which may be only aboutone-half inch or about 1.3 cm thick. Also, to provide adequate strengthand compactness, the brace and it components are preferably made of highstrength material such as steel, titanium, zinc alloys, or other highstrength metals or high strength plastic.

It is further noted that, in the preferred design, two catch plates areprovided, and each of the stop assemblies includes a pin which seats incorresponding recesses in each of the two catch plates, to provide abalanced locking configuration for resisting forces applied between thestruts to limit flexion or extension. The inner and outer cover platesmay also have complementary recesses to more positively secure the stopsat the selected angular position.

Referring back to the overall construction as mentioned above, one strutextends from the knee pivot assembly up the upper leg or thigh, and theother strut extends from the pivot assembly down the lower leg. Thepivot stop assembly is mounted on the end of a first one of thesestruts, and the second strut has stop surfaces on its end adjacent thestop assembly which engage the flexion and extension stops. Further, thecatch plates as described above are mounted on opposite sides of thissecond strut, with the locking member of the movable stop assemblyengaging locking steps on both of the two catch plates, so that abalanced positive stopping force is transmitted to the second strut whenthe stop surfaces on the end of the second strut engage the flexion stopor the extension stop.

Additional aspects of the knee brace may include the following:

-   -   (1) catch plates which have separate sets of notches for the        flexion and extension stops, and a mechanical coupling between        these two sets of notches;    -   (2) Color coded flexion and extension actuation buttons, with        the degree indicia set forth in matching different colors;    -   (3) Apertures or holes in the actuation buttons to permit        locking of the buttons against change.

Other objects, features and advantages of the invention will becomeapparent from a consideration of the drawings and from the detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a knee brace assembly illustrating theprinciples of the invention;

FIG. 2 is a plan view of one of the two knee braces included in the kneebrace assembly of FIG. 1;

FIG. 3 is a side view of the knee brace of FIG. 2;

FIG. 4 is an enlarged plan view of a knee brace pivot and motionlimiting assembly, illustrating the principles of the invention;

FIG. 5 is an enlarged perspective view of the pivot assembly;

FIG. 6 is an exploded view of the knee brace assembly illustrating theprinciples of the invention;

FIG. 7 is an enlarged view of the central pivot and stop assembly of theknee brace of FIGS. 1-6, with the front cover removed;

FIG. 8 is an exploded view of the two movable stops and their associatedadjustment buttons, and indication support members;

FIGS. 9-12 show various stop adjustment configurations for the kneebrace;

FIG. 13 is an exploded perspective view of an alternative embodimentknee brace assembly;

FIG. 13 a is a cross-sectional view showing the interaction of thedetent and the adjustment hole of the strut extension; and

FIG. 14 is an exploded perspective view of the hinge assembly for theknee brace shown in FIG. 13.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the specification describes particular embodiments of the presentinvention, those of ordinary skill can devise variations of the presentinvention without departing from the inventive concept.

Referring more particularly to the drawings, FIG. 1 shows a leg brace 12for the knee, including two struts extending up and down the leg from acentral pivot assembly 14. Extending along the upper leg is a strut 16,and extending down the lower leg from the pivot assembly 14 is a lowerstrut 18. These struts are sometimes referenced as femoral struts (asextending along the femur or upper leg bone) and tibial struts(extending along the tibia, or the principal lower leg bone). A pivotassembly on the other side of the knee is also provided with strutsextending up and down the leg, but these are not visible in FIG. 1.

To hold the struts in place on the leg are a series of straps 22 on theupper leg, and straps 24 on the lower leg. Suitable padding 26 isprovided on the upper leg, and the struts are normally secured to thepadding 26 by appropriate VELCRO® or hook and loop type material.Similar padding 28 underlies the strut 18 and straps 24. The straps 22extend through the loops 38 to hold the entire assembly together underactive usage conditions.

The present invention is directed primarily to the pivot stop assemblieswhich interconnect the struts. For a post-operative patient, it isdesirable to be able to limit the bending of the knee both in theextension direction when the patient is straightening his or her leg,and in the flexion direction where the patient is bending the leg at theknee as far as practical under the circumstances.

The showing of FIG. 1 is of the outside of the left leg. On the insideof the left leg is a similar assembly, to that shown in FIG. 1, with twostruts and a central pivot assembly. The two units are similar and bothare held to the leg by the straps 22 and 24. Most of the parts arecommon to the inner and outer assemblies, but with the struts and thecover plates being mirror images of one another.

To better understand the operation of the entire assembly, it is usefulto refer briefly to the exploded view of FIG. 6. In operation, the twostruts 16 and 18 are pivoted relative to one another about center rivet56; and strut 18 has two stop surfaces 32 and 34. Adjustable stops aremounted to the hinge pivot assembly 14 on strut 16 and the adjustablestops engage stop surfaces 32 and 34 to limit pivoting of the knee inboth the extension and the flexion directions.

FIG. 2 of the drawings shows the assembly 12 and the pivot assembly 14with the straps 22 and 24, and the padding 26 and 28 removed. Visible inFIG. 2 are the strap coupling members 36 which are secured to thestruts, and the strap receiving openings 38. FIG. 3 is a side view ofthe assembly of FIG. 2. The pivot assembly 14 will be described ingreater detail hereinbelow.

Referring now to FIGS. 4 and 5 of the drawings, these are plan andperspective views, respectively of the pivot assembly 14 whichinterconnects the struts 16 and 18.

Now, considering FIG. 4 in detail, it includes the extension stopassembly 42 and the flexion stop assembly 44. Visible on the cover plate46 are degree indicia which may be read through the openings 48 and 50on the stop assemblies 42 and 44, respectively. To change the limits ofmotion, the push buttons 52 and 54 are depressed and the stop assembliesare rotated to the desired angular settings. Incidentally, the outermostsurfaces of push buttons 52 and 54 are preferably knurled, ribbed ortextured for non-slip engagement. Alternatively the stops may be coatedwith a frictional coating.

Concerning the angular settings, when the extension stop 42 is at zerodegrees (0°), the patient is free to fully extend his lower leg. Whenthe extension stop 42 is set to 90°, the lower leg is restrained frommovement beyond 90° relative to the upper leg, so the lower leg cannotbe straightened out.

Regarding the flexion stop 44, when it is set to 120° the lower leg maybe fully bent toward the upper leg. When the flexion stop is set to“lock”, then the lower leg is fully extended, and is blocked from anybending. If both stops 42 and 44 are set to 60° for example, the knee isheld at 60° from fully open, and is restrained from movement in eitherdirection.

Incidentally, the support members for the stops are both pivoted aboutthe center 56 of the pivot assembly 14, with the reference number 56representing the head of a rivet extending through the assembly.

Consideration will now be given to the detailed construction of thepivotal stop mechanism, by reference to the exploded view of FIG. 6. Asmentioned above, one of the two struts 18 has the two stop surfaces 32and 34 on its end, and is pivoted, with opening 62 receiving rivet 56which extends through the entire assembly. The flat parts 64 and 66 arespacers and also serve the function of washers in facilitating rotationof the overlying parts. They may be formed of plastic such as nylon. Thecatch plates 68 and 70 have a series of inwardly opening recesses whichreceive outwardly biased locking pins as described below.

The inner cover plate 72 and the outer cover plate 74 may also beprovided with inwardly directed recesses, matching those in the catchplates 68 and 70. This provides supplemental restraint for the lockingpins shown in detail in later figures of the drawings.

FIG. 7 is an enlarged view of the central mechanism with one of thecover plates removed. The stop assembly 44 has a locking pin 82 whichmoves inward with the push button 54 to change settings, but is springbiased outward to engage one of the recesses 84. Similarly, the lockingpin 86 associated with push button 52, locks the stop 42 by engagementwith a selected one of the catch plate recesses 84.

FIG. 8 is an enlarged showing of the physical stop members 92 and 94which engage the stop surfaces 32 and 34 as shown in FIG. 6. Two smallpairs of coil springs 96 and 98 serve to bias the push buttons 52 and54, and the associated locking pins 86 and 82 outward, into engagementwith the catch plate 68 (see FIG. 7) and the other catch plate 70 (seeFIG. 6).

Incidentally, the physical stops 92 and 94 may be formed of a highstrength zinc alloy referenced as ZA-28, or other high strengthmaterial.

FIGS. 9 through 12 shows various adjustments of the stops, and theresultant permitted positions of the struts 16 and 18. Morespecifically, FIG. 9 shows the extension stop 42 and the flexion stop 44in their positions for full range of motion, with the extension stop 42at 0° and the extension stop 44 at 120° (see FIG. 4). In FIG. 9 thestruts (and the leg) are fully extended; while in FIG. 10, the strutsand the leg are bent to their extreme flexed position, with the twostops in the same positions for both FIG. 9 and FIG. 10.

FIG. 11 is a similar pair of drawings with the extension stop at about45° and the flexion stop at about 75° in both figures. In FIG. 11 thestruts are extended as far as possible with this setting of stops 42 and44; and in FIG. 12 the struts (and leg) are bent as far as permittedwith this setting of the stops 42 and 44.

An alternative embodiment of the stop mechanism may include a physicalstop having a radially extending slot for receiving a locking pinassociated with a push button; and a wire spring biasing the push buttonand locking pin radially outward relative to the stop support members.

Concerning another matter, with reference to FIG. 4 of the drawings, thepush buttons 52 and their associated assemblies are preferably colorcoded to match colored angle indicia. Thus, push button 52 may becolored blue, with the associated degree indicia from “0” to “90”degrees being the same blue color; and push button 54 and associatedindicia may be colored green.

It may be noted that the push buttons are provided with holes near theouter ends thereof. This permits the physician or technical assistant tothread wire or plastic ties through the openings to discouragere-setting or tampering with the angular settings, as shown at referencenumerals 101 and 103 in FIGS. 11 and 12 of the drawings. Other elementsfor preventing or restricting actuation of the push buttons, includinglocking ties, may be employed; and these elements may be separate fromor integral with and movable with respect to, the knee brace assembly.

FIG. 13 is an exploded perspective view of an alternative embodimentergonomic knee brace having extendable struts 100 for convenient lengthadjustments. Specifically, in the embodiment shown in FIG. 13, an upper(femoral) strut assembly 102 is joined to a hinge assembly or pivotingarrangement 104. A lower (tibial) strut assembly 106 is also joined tothe hinge assembly 104. Each strut assembly 102, 106 is preferablyriveted at one end to the hinge assembly 104 via one or more rivets 108and respective washers and/or lock nuts 110. Other mechanical fastenersor linkages may be used to join the components as well as the use ofadhesives, welding, brazing, or the like.

Each strut assembly 102, 106 preferably includes a strut sleeve 112,114. The strut sleeve 112, 114 is preferably made from a molded plastichaving a generally rectangular cross-section with a rectangular channel,slot, or hole 166 extending through the center. The rectangular hole 166of the strut sleeves 112, 114 is designed to slidably receive respectivestrut extensions 116, 118. Each strut extension 116, 118 is preferablymade from a rigid material such as steel and includes a series of spacedapart length-adjustment holes 120. The preferred elongated flat plateshape of the strut extensions 116, 118 allows the extensions to easilyslide in and out of the respective strut sleeves 112, 114 therebyadjusting the overall lengths of the upper and lower strut assemblies102, 106. As seen in FIG. 13, markings such as numerals, hash marks, andother indicia can be placed on the strut extensions 116, 118 to guideand assist in repeatably and quickly setting up the desired length ofthe strut assemblies 102, 106.

Once the desired length of the strut extension 116, 118 is found, ascrew-in knob or lock level 122 is turned preferably 180° clockwisemanually to lock the strut extension 116, 118 to the respective sleeve112, 114 thus inhibiting further relative sliding. To do this, thescrew-in knob or lock lever 122 includes a post 124 extending underneathhaving threads thereon that engage threads in the sleeve 112, 114 andthat advance the post 124 into one of the adjustment/receiving holes 120of the respective strut extension 116, 118. This is shown in thecross-sectional view of FIG. 13 a. The screw-in lever 122 preferably hasa low profile, elongated lever-like shape so that via manual twistingaction by the user, sufficient torque is generated to advance the post124 into the respective strut extension adjustment hole 120. A lowprofile prevents inadvertent operation of the screw-in lever 122 byaccidental brushing against clothing, the wearer's limb, or furniture,for example. For better grip, the upper surface of the lever 122 may betextured.

To unlock the strut extension 116, 118 from the strut sleeve 112, 114,an opposite turn of the screw-in lever 122 withdraws the post 124 fromengagement with the hole 120. The strut extension and its sleeve can nowfreely slide relative to each other.

To provide sufficient strength, the screw-in lever 122 and strut sleeves112, 114 are preferably made from glass filled nylon or like polymers.The strut sleeves may have an aluminum, steel, or like metal skeletonover which the plastic is molded if more strength is desired.

Because the adjustment holes 120 of the strut extensions 116, 118 arecovered by the strut sleeves 112, 114 when the two parts are assembled,the user or wearer is not able to easily align the post 124 with thedesired adjustment hole 120 to interlock the sleeve and extensiontogether. To enhance easy alignment of the post 124 and adjustment hole120, the preferred embodiment strut sleeve 112, 114 has one or moredetents 126 formed into the interior surface at the bottom of therectangular opening 166. This is shown in the cross-sectional view inFIG. 13 a.

Therefore, as each adjustment hole 120 slides past the detent 126, thereis noticeable click-stop that can be felt and heard by the userindicating that the post 124 and one of the adjustment holes 120 arealigned. In the preferred embodiment, the detent 126 is a bump, ridge,ramp, or like click-stop that slightly enters and easily slides out ofany one of the adjustment holes 120 of the strut extension 116, 118.Preferably, the detent 126 is formed from the material used to createthe strut sleeve 112, 114, and more preferably, the detent 126 is apartial cutout of the sleeve bottom to form a cantilevered springconfiguration shown in FIG. 13 a. That is, the detent 126 is an inwardfacing bump positioned at the end of an elongated, rectangular springboard whose shape is defined by three-quarters peripheral cut with abase still attached to the sleeve 112, 114. This cantilevered springconfiguration for the detent 126 creates even greater verticalcompliance allowing the bump of the detent 126 to engage and disengagethe adjustment hole 120 for improved tactile and audible indications yetdoes not significantly impede the strut extension sliding action insidethe strut sleeve 112, 114. One or more detents 126 may be used in eachsleeve and/or for each hole.

To prevent the user from accidentally overly twisting the screw-in lever122, an optional turn stop 172 positioned on the surface of the sleeve112, 114 blocks the outer limit of rotational travel of the screw-inlever 122. FIGS. 13 and 13 a show such a stop 172. The preferredembodiment turn stop 172 has a ramp-like profile with a flat engagementface that is designed to engage the rotating screw-in lever 122. Thus,the screw-in lever 122 as shown in FIG. 13 can be rotated clockwisethrough about 270° and more preferably about 180° of travel untilencountering the rising resistance of moving up the ramp of the turnstop 172, and the screw-in lever 122 can be rotated about 2700 and morepreferably about 180° counterclockwise until it encounters the flatengagement face at the opposite side of the turn stop 172. The pitch ofthe threads for the post 124 is selected so that about a 270° and morepreferably about 180° clockwise turn is sufficient to fully engage thepost 124 with the adjustment hole 120. Of course, smaller or largerangular turns of the screw-in lever 122 to lock and unlock thecomponents are contemplated. The preferred 180° rotational range tolock/unlock the screw-in lever 122 is selected for ergonomics and easeof use of the knee brace wearer.

Although in the exemplary embodiment shown the detent engages the strutextension and adjustment holes from the bottom of the sleeve, it ispossible to have detents that engage the strut extension and adjustmentholes from the top or from the side, assuming the edge of the strutextension has been cut or formed with a series of notches, pits, orindentations to achieve the click-stop action.

An assortment of curled cuffs 128 optionally having laterally extendingD-rings can be mounted, fastened, molded, or glued to the strutassemblies 102, 106. In the exemplary embodiment shown in FIG. 13, asingle cuff 128 is fastened to the very distal end of the upper strutextension 116, and likewise a cuff 128 is attached to the distal end ofthe lower strut extension 118. The upper strut sleeve 112 includes twocuffs 128 molded integrally with the sleeve while the lower strut sleeve114 has a cuff 128 molded integrally with the sleeve with a second cuffthat can be attached thereto. Adjustable straps (not shown) with VELCRO®fasteners, buckles, and the like can then be looped through the D-ringsof the cuffs 128. The straps are used to attach the knee brace to thepatient's leg. The large surface area of the cuffs 128 helps withfitment of the ergonomic knee brace 100 to the patient's leg andminimizes shifting of the leg within the knee brace. Optionally, agastrocnemius strap 168 with a snap 170 at one end is provided with theknee brace 100. The snap 170 selectively attaches the gastrocnemiusstrap 168 to an eyelet or blind hole in the strut sleeve 112, and moreprecisely to the superior or calf cuff 128′. When attached to the strutsleeve 112, the strap 168 is worn around the calf area of the patient'sleg and helps suspend the knee brace 100 to the leg.

The alternative embodiment knee brace shown in FIG. 13 further includesa drop lock feature that can quickly and easily lock down the relativepivoting motions of the upper and lower strut assemblies 102, 106.Specifically, a sliding drop lock button 130 is preferably located onthe hinge assembly 104 that when slid into its locking position, itinterlocks the upper and lower strut assemblies 102, 106 to inhibit thepivoting action.

To quickly and repeatably locate the desired flexion angle of the kneewhen the drop lock can be used, the lower strut sleeve 114 optionallyhas a sloped face 132 opposite to the location of the drop lock button130, essentially on opposite sides of the hinge assembly 104. Thisarrangement provides a sloped face 132 with flexion angle markings thatare visible to the wearer of the knee brace or to a nurse when he or shelooks downward on the knee brace 100 when locking down the pivotingaction with the drop lock button 130. As in the previous embodiments,the hinge assembly 104 includes a flexion stop 134 and an extension stop136 that sweep about the hinge assembly 104. With the drop lock button130 disengaged, the upper and lower strut assemblies 102, 106 are freeto pivot within the defined angular limits set by the flexion andextension stops 134, 136. Advantageously, the pivoting-action-lockoutvia the drop lock button 130 and the flexion and extension stops 134,136 are all centrally congregated at the hinge assembly 104.

FIG. 14 is an exploded perspective view of the hinge assembly 104 fromthe alternative embodiment knee brace shown in FIG. 13. The principle ofoperation of the flexion and extension stops 134, 136 are as describedin the preceding embodiments. As seen in the exploded view of FIG. 14,the hinge assembly 104 is a collection of preferably two disk-like catchplates 138, 140. Each catch plate 138, 140 has a series of recesses orteeth 154 located at the outer periphery of circumferentially extending,arcuate-shaped slots. The catch plates 138, 140 are mounted to theproximal ends of the lower strut assembly 106 and the upper strutassembly 102. The remaining structures of the respective strutassemblies have been omitted from FIG. 14 for ease of illustration. Bothproximal ends of the lower strut assembly 106 and the upper strutassembly 102 freely pivot against each other. The internal workings ofthe hinge assembly 104 are enclosed by an outer cover plate 142 and aninner cover plate 144. The flexion stop 134 and the extension stop 136are mounted to the hinge assembly 104, and each extension or flexionstop 134, 136 has a stop release button 146 that is biased by a spring152 away from a stop base 148 wherein a lock pin 150 extending throughthe stop base 148 selectively engages to the teeth 154 formed in thecatch plates 138, 140. By pushing radially inward on the extension orflexion stop release button 146 against the bias of the spring 152, thelock pin 150 is disengaged from the teeth 154 allowing the extension orflexion stop base 148 to be moved along the circumferential slots formedin the catch plates 138, 140. This movement enables adjustment theflexion or extension stop angles. Once the finger pressure is releasedfrom the extension or flexion stop release button 146, the spring biasforces the lock pins 150 radially outward to again engage the teeth 154in the catch plates 138, 140. A center rivet 156 acts as a hub for thehinge assembly 104 and holds the entire assembly together.

FIG. 14 also shows the preferred construction of the drop lock button130 that is slidably mounted to the surface of the outer cover plate142. The drop lock button 130 engages a drop lock base 158 which is heldin place by a horseshoe shaped spring 160, which components are then fitinto the upper strut assembly 102 as shown. One or more ribs 162 extendfrom the drop lock base 158. The ribs 162 selectively engage one or morestop recesses or teeth 164 formed at the proximal end of the lower strutassembly 106. Thus, by sliding the drop lock button 130 radially inwardor outward, the drop lock base 158 moves toward or away from the teeth164 thereby engaging or disengaging the ribs 162 with the teeth 164. Ifengaged, the engage between ribs 162 and teeth 164 interlocks the lowerstrut assembly 106 to the upper strut assembly 102 thereby inhibitingthe relative pivoting action of the two components. The horseshoe spring160 pinches on the drop lock base 158 to provide some bias to hold thedrop lock base 158 in either the engaged or disengaged positions.

It is to be understood that the foregoing detailed description disclosesone preferred illustrative embodiment of the invention, Various changesand modifications may be made without departing from the spirit andscope of the invention. Thus, by way of example and not of limitation,instead of having catch plates with locking recesses, a series ofoutwardly extending rods or protrusions may be provided, with the stopbuttons having an outwardly biased fork member for engaging the rods andthereby positioning the stop body or stop plate in the desired angularposition. In addition, while the disclosed configuration of the stopsupports 44 and 48 is preferred, the stop assemblies may be pivotallymounted within the cover plates as well as, or instead of extending overthe outer surface of the outer cover plate. With regard to anothermatter, the release push button may be integral with the physical stops.Also, the various parts may be replaced by their mechanical equivalents,such as rivets being replaced by threaded fasteners, or the like.Accordingly, the present invention is not limited to the preciseembodiments described in detail hereinabove, and shown in theaccompanied drawings.

1. An orthopedic device, comprising: a first strut having a first stopsurface; a second strut having a second stop surface; a hinge forrotationally coupling said first strut and said second strut relative toone another, said hinge defining a center axis and including stopassemblies for first and second rotational directions, the hingeincluding: (a) a hinge plate forming an arcuate array of stop recessesfacing or opening toward the center axis of said hinge; (b) a movablestop pivoted about the center axis and having a stop member, anoutwardly biased locking member for engaging the stop recesses andslidably biased within and relative to the stop member, and a releasebutton connected to the locking member and slidably biased within andrelative to the stop member, the release button extending radiallyoutwardly beyond the periphery of the hinge plate and being movableinwardly to shift the locking member out of the stop recesses to permitangular adjustment of the stop; wherein the stop is arranged to engagewith at least one of the first and second stop surfaces.
 2. Theorthopedic device according to claim 1, wherein the movable stop has anouter portion extending over a circular outer surface of the hingehaving angular indicia printed in arcuate array.
 3. The orthopedicdevice according to claim 2, wherein the outer portion of the movablestop has a window aligned with the angular indicia, the stop beingadjustable to selected angular positions.
 4. The orthopedic deviceaccording to claim 1, wherein the stop defines a plate portion forming acentral opening configured to align with the center axis.
 5. Theorthopedic device according to claim 1, wherein the stop member definesan extension portion radially spaced from the center axis, the extensionincluding the locking member and the release button.
 6. The orthopedicdevice according to claim 1, wherein the stop includes a springcontained in the stop member and biasing the locking member and releasebutton away from the center axis.
 7. The orthopedic device according toclaim 1, wherein the stop defines a plate portion forming a centralopening configured to align with the center axis.
 8. The orthopedicdevice according to claim 1, wherein the stop defines an extensionportion radially spaced from the center axis, the extension includingthe locking member and the release button.
 9. A hinge assembly fororthopedic use, the hinge having a center axis and assemblies for firstand second rotational directions, comprising: first and second armshaving first and second stop surfaces, respectively; a hinge plateforming an arcuate array of stop recesses facing or opening toward thecenter axis of said hinge, the hinge plate connecting to the first andsecond arms; a movable stop pivoted about the center axis and having astop member, an outwardly biased locking member for engaging the stoprecesses and slidably biased within and relative to the stop member, anda release button connected to the locking member and slidably biasedwithin and relative to the stop member, the release button extendingradially outwardly beyond the periphery of the hinge plate and beingmovable inwardly to shift the locking member out of the stop recesses topermit angular adjustment of the stop; a spring contained in the stopmember and biasing the locking member and release button away from thecenter axis; wherein the stop is arranged to engage with at least one ofthe first and second stop surfaces.
 10. The orthopedic device accordingto claim 9, wherein the movable stop has an outer portion extending overa circular outer surface of the hinge having angular indicia printed inarcuate array.
 11. The orthopedic device according to claim 10, whereinthe outer portion of the movable stop has a window aligned with theangular indicia, the stop being adjustable to selected angularpositions.